This was then compared to the childrens' academic performance in the National Assessment Program - Literacy and Numeracy (NAPLAN) test.

The study found a relationship between academic performance and the fitness of the child, confirming findings from other studies.

But, uniquely, this study found that the relationship between fitness and academic performance was particularly strong at the school level.

Telford says while fitness may affect performance through physiological changes, the findings show there is also a parallel effect of school culture on academic performance.

"Our results certainly show there's a relationship between physical activity and fitness and the academic performance," says Telford. "But because it's stronger at the school level, I'm saying a major reason for this is a cultural effect at the school."

Telford says school culture involves the principal, the parents' association as well as the teachers all encouraging fitness as well as academic achievement.

"The best teachers of literacy and numeracy happen to be the very same teachers that understand how important it is for a kid to be physically active for their health," says Telford.

In a separate study, Telford and colleagues looked at the effect of children being taught physical education by special PE teachers, instead of general classroom teachers.

They found those students taught by specialised PE teachers scored 10 to 13 points higher on the NAPLAN test scores.